Hi all, First post here.. I have a '92 F150 4x4 running a 300 EFI and a 5 speed manual transmission. It's a great little truck aside from one thing - it has some sort of glitch that I can'f figure out. First opf all - I am not fond of computers and all of the sensors on newer vehicles but of course this truck has both. When I bought the truck a year ago, I was told that in order for it to start properly, you had to engae the starter, shut the ignition switch off and then turn the key to start and engage the starter and the engine would fire right up. And they were right. If I try to start it with the first turn of the key, it does not want to start and just cranks over. OK.. I can live with that.
Here's the big one.. I usually just use the truck for my daily driver to and from town and I find that when I start out from a cold start, the engine seems to pull not too bad. As I get up towards highway spped, it staryts to crap out and is definiotely short of power until I depress the clutch and very quickly turn the ignition off and then back on - not even giving the engine a chance to stop running - just a real quick off and on of the switch, and then away it goes. SOmetimes, it seems not too bad but will start to jerk and screw around once I get up to highway cruising speed ( 50 MPH here ) but if I do the old off and on trick, it levels right out and away we go. I have changed the fuel filted and O2 sensor - it is definitely better - but it still screws around.
This evening, I loaded it up with a fairly heavy load ( for this truc anyways ) of firewood and my son ran the battery low playing around with the radio and lights. I thought thatthe battery was better than it is - obviously, I ammistaken, I pulled the cables off the battery thinking that there was a bad connection - there was not. I hooked the battery up again, got a boost and we started for home. The truck jerked and fought me all the way home - most of the way in second and third gear. It idles fine and it pulls fine up to a point and then the jerking and bucking starts. I do not know if this is because I unhooked the battery and did not go ghtough some ritual that only a Ford engineer understands before starting it or if it is because of the heavy load.
Sometimes I think thatthis is a fuel problem and at other times, it;s like it is electrical with the off and on thing with the ignition. Any ideas? Any suggestions will be appreciated.

 

First, pull codes: www.fordfuelinjection.com is a bookmark worthy website. Second, have the fuel pressure on the rail checked as it sounds like it could be a fuel issue to me as well. Pull the vacuum line on the fuel pressure regulator and check for fuel inside of it...if there's fuel in it, replace it. make sure you know which FPR you have as there's two different style. Let us know what you get pressure-wise at the rail KOEO and KOER.

 

Thanks for the information and I'll read through the site and see what I can find that makes sense to me. I've got all kinds of tools but I don't own any of the fancy stuff for fuel injection and computers, so I'll have a friend who probably has a pressure guage check the fuel pressure in the next day or so once I get the firewood unloaded. I'll have to try to catch him at his shop as he is only there by chance and set up a time. I'll be sure to post the results. I can understand why this could be a fuel pressure issue but wouldn't the having to switch the ignition switch quickly off and then on again to help the engine have more power indicate an electrical issue? Man, but I hate this computerized stuff with all it's sensors and crap. Guess I am getting too old for this kind of frustration. I'm thinking strongly of going back to my old truck with a carburetor and absolute minimal electronics. The thing that I like the most about this truck is the fuel economy - it's really affordable to run and I know that my old '77 F150 Super Cab can't even come close. I miss my old truck....